feat: multi-language interface (zh-CN/zh-TW/en/ja), multilingual offline changelog, settings robustness

i18n
- shared/i18n: dependency-free t() with flat per-namespace dictionaries
  (common/settings/workspace/terminal/ssh/panels/main), zh-CN fallback
- language picker in Settings -> System; antd ConfigProvider locale follows it
- main process tracks the language too: tray menu, close prompt, ssh/sftp/
  zmodem errors and the log TUI marker are translated; tray rebuilds on change

changelog
- CHANGELOG.md (zh-CN canonical) + .zh-TW/.en/.ja, bundled via ?raw and read
  per interface language with per-version fallback to zh-CN (no network)
- sync-changelog.cjs merges RELEASE_NOTES[.<lang>].md per release; release.cjs
  refuses to publish without a zh-CN entry for the version

settings robustness
- closeAction 'ask' survives the sanitizer (was silently coerced to 'tray',
  which made the 'ask every time' option dead)
- highlight rules are repaired instead of dropped: string priority, 0/1
  enabled, missing fg colour; unknown fields preserved
- load-time warnings are written to settings-warnings.log (deduped, capped)

terminal/UI
- configurable terminal toolbar: open working directory (default on), session
  log recording (off), open logs folder (off)
- global shortcut field records key combos (modifier or F-key required)
- input suggestions + command history default to off, with a one-time reset
  migration for existing installs
- settings dialog scrolling fixed (antd v6 renamed the tabs container), theme
  gallery nested scrollbar removed, joined segmented pickers with readable
  selected-state text

tests: settings-store.mjs (15 checks) added; commands-store.mjs updated for
the new off-by-default history setting

src/main/index.ts

@@ -4,9 +4,10 @@ import { join } from 'path'
 import { registerIpc } from './ipc'
 import { killAllPtys } from './pty'
 import { applyStartupSystemSettings, loadSettings } from './settingsStore'
-import { initTray, markQuitting, onMainWindowClose } from './tray'
+import { initTray, markQuitting, onMainWindowClose, refreshTrayMenu } from './tray'
 import { configureAutoUpdater, registerUpdateIpc } from './updater'
 import { applyWindowChrome } from './windowChrome'
+import { onLanguageChange } from '@shared/i18n'
 import { getThemeById } from '@shared/theme'
 
 /** Re-create the main window (tray restore path after all windows are gone). */
@@ -122,6 +123,9 @@ app.whenReady().then(() => {
   applyStartupSystemSettings(loadSettings())
   createWindow()
   initTray(showOrCreate)
+  // Tray labels are resolved from the dictionary at build time, so the menu has
+  // to be rebuilt whenever the interface language changes.
+  onLanguageChange(() => refreshTrayMenu())
   configureAutoUpdater()
 
   app.on('activate', () => {